CONTENTS. 
—__+—_ 
PREFACE , . 
LIST OF WOODCUTS . : : ‘ : : . 6 » 
CHAPTER I. 
THe NatTuraL Hisrory oF THE CoMMON CRAYFISH . a 3 
CHAPTER II. 
THE PHYSIOLOGY OF THE ComMMON CRAYFISH. THE Mecmawten 
BY WHICH THE Pants OF THE LivING ENGINE ARE SUPPLIED 
WITH TIIE MATERIALS NECESSARY FOR THEIR MAINTENANCE 
AND GROWTH . i : s . 7 
CHAPTER III. 
THE PHYSIOLOGY OF THE CoMMON CRAYFISH. THE MECHANISM 
BY WHICH THE LivING ORGANISM ADJUSTS ITSELF TO SUR- 
ROUNDING CONDITIONS AND REPRODUCES ITSELF . . 
CHAPTER IV. 
THE MorPHOLOGY oF THE CoMMON CRAYFISH. THE STRUCTURE 
AND THE DEVELOPMENT OF THE INDIVIDUAL . : Sos 
PAGE 
xi 
46 
87 
137 
